In this study, a novel and highly reactive Sn–Pd catalyst supported by environmentally benign kaolinite (Sn–Pd-kaolinite) was developed and evaluated for stability for effective nitrate (NO3−) reduction in batch and continuous mode. Complete NO3− removal with fast reduction kinetics (k = 18.16 × 10−2 min−1) and 71% selectivity toward N2 were achieved by the Sn–Pd-kaolinite catalyst during batch reactions. During continuous tests, 100% NO3− removal and 80% N2 was achieved for 60 h. However, NO3− removal efficiency gradually decreased to 80% in170 h. The catalyst was then successfully regenerated in the system by increasing H2 flow which achieved a complete NO3− removal again. The metal leaching from catalyst surface was negligible (Sn 0.01% and Pd 0.006%) and the structure was stable during the continuous test, confirming that the Sn–Pd-Kaolinite catalyst had a superior reaction kinetics and operational durability.
Bibliographical noteFunding Information:
The authors are sincerely thankful to all collaborators who can make this wonderful research achievement possible in the Global Environmental Geobiochemical Research Laboratory (EGRL) at Nazarbayev University and help start its wonderful scientific journey again. The research has been supported by Nazarbayev University Research Grants (Contract No. 284–2019//012–2019 and 076–2018 ). Appendix A
© 2019 Elsevier Ltd
All Science Journal Classification (ASJC) codes
- Environmental Engineering
- Environmental Chemistry
- Health, Toxicology and Mutagenesis